An attachment for a prime mover

ABSTRACT

An attachment (60) for a wheeled work vehicle (2) for clearing snow comprises a support housing (3) which rotatably carries an elongated cylindrical brush (5) and a plough blade (4), with the plough blade (4) and the brush (5) alternately operable between a lower operative state and an upper inoperative state. End elements (62) are pivotally coupled about vertical pivot axes adjacent respective opposite ends (15,16) of the plough blade (4). The end elements (62) are pivotal about a main vertical pivot axis (64) between a plurality of forward and rearward states through respective outward states. A coupling mechanism (7) couples the attachment (1) to the wheeled work vehicle (2) so that the support housing (3) is slewable between a transverse state and respective maximum offset states. When the housing (3) is in the transverse state with the plough blade (4) in the transverse state, the end elements (62) may be configured in a plurality of working states relative to the plough blade (4), for example, with the end elements (62) in respective first forward states, in respective first rearward states and with one of the end elements in an outward state and the other in a first forward or a first rearward state. When the support element (3) is in one of the offset states with the plough blade (4) in a corresponding offset angled state relative to the transverse state, the end elements (62) are operable in a plurality of working states including second forward and rearward states with the end elements extending either forwardly or rearwardly relative to the plough blade (4) and parallel to the direction of normal forward motion of the wheeled work vehicle (2) or in respective outward states extending outwardly and substantially aligned with the plough blade (4).

The present invention relates to an attachment for a prime mover, for example, for attaching to a wheeled work vehicle, for clearing snow, debris and other material from a roadway, an airport runway, an apron around arrival and departure gates of an airport where aircraft stand during boarding and disembarking thereof.

Such attachments for a prime mover are known, and typically comprise a support housing which is coupled to the prime mover, such as, for example, a fixed chassis tractor or a wheeled work vehicle of the type comprising a forward part and a rearward part with the forward and rearward parts pivotally connected together about a substantially vertical pivot axis for facilitating steering of the wheeled work vehicle. The support housing of such attachments typically comprise an elongated cylindrical brush which is rotatably mounted in the support housing about a geometrical central rotational axis, and an elongated plough blade which extends substantially parallel to the rotational axis of the brush. The plough blade may be coupled to the support housing to be operable in a lower operative state for engaging or adjacent the ground for clearing the material to be cleared and a raised upper inoperative state spaced apart above the ground and above the material. The brush may also be operable between a lower operative state for brushing material along the ground, and a raised upper state with the brush spaced apart above the ground.

The coupling mechanism which couples the attachment to the prime mover may be configured for slewing the support housing and in turn the brush and the plough blade between a transverse state extending transversely relative to the direction of normal forward motion of the prime mover, and an offset state with the plough blade extending at an offset angle relative to the transverse state of the plough blade. However, such attachments suffer from various disadvantages, for example, the plough blade may be of a fixed length, and in certain cases a longer or a shorter plough blade may be required, which requires replacing the plough blade with a plough blade of the desired length. Additionally, it may or may not be desirable to prevent spilling of material from one or both ends of the plough blade.

There is therefore a need for an attachment for a prime mover which comprises an elongated cylindrical brush and a plough blade which addresses at least some of the problems of such known attachments.

The present invention is directed towards providing such an attachment for a prime mover, and the invention is also directed towards providing a prime mover comprising the attachment. Further the invention is directed towards a method for operating an attachment coupled to a prime mover.

According to the invention there is provided an attachment for a prime mover, the attachment comprising a support element, an elongated generally transversely extending cylindrical brush rotatably mounted in the support element about a substantially transversely extending rotational axis, an elongated generally transversely extending plough blade supported on the support element, a pair of end elements located at respective opposite ends of the plough blade, each end element being selectively operable relative to the plough blade in at least a first forward state extending generally forwardly and substantially perpendicularly from the plough blade and a first rearward state extending generally rearwardly and substantially perpendicularly from the plough blade, the end elements being selectively operable in a first working state with both of the end elements in the first forward state, a second working state with both of the end elements in the first rearward state, and a third working state with one of the end elements in the first forward state and the other one of the end elements in the first rearward state, and a coupling means for coupling the support element to a prime mover with the support element in a transverse state and with the plough blade and the brush extending substantially transversely of the direction of normal forward motion of the prime mover.

In one aspect of the invention each end element is selectively operable in an outward state with the end element extending generally outwardly from the plough blade and substantially longitudinally aligned with the plough blade.

In another aspect of the invention the end elements are selectively operable in a fourth working state with one of the end elements in the outward state and the other one of the end elements in one of the first forward state and the first rearward state.

Preferably, the end elements are selectively operable in a fifth working state with both the end elements in the outward state.

Advantageously, each end element is selectively operable in a plurality of intermediate states intermediate the outward state and the first forward state.

Ideally, each end element is selectively operable in a plurality of intermediate states intermediate the outward state and the first rearward state.

Preferably, each end element is selectively operable in a plurality of intermediate states between the first forward state and the first rearward state.

In another aspect of the invention the coupling means is configured for selectively setting the support element relative to the prime mover in the transverse state with the plough blade and the brush in the transverse state extending substantially transversely of the direction of normal forward motion of the prime mover and a maximum offset state with the plough blade and the brush in a maximum offset angled state offset at an angle greater than zero from the transverse state thereof.

In another aspect of the invention the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is at least 10°.

Preferably, the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is at least 20°.

Advantageously, the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is at least 30°.

Ideally, the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is up to 35°.

In another aspect of the invention the support element is selectively operable in a plurality of offset states between the transverse state thereof and the maximum offset state thereof with the plough blade and the brush in a corresponding offset angled state.

In a further aspect of the invention each end element is selectively operable in a second forward state extending from the plough blade generally forwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state.

In another aspect of the invention each end element is selectively operable in a second rearward state extending from the plough blade generally rearwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state.

Preferably, the end elements are selectively operable in a sixth working state with one of the end elements in the second forward state, and the other one of the end elements in the second rearward state.

Advantageously, the end elements are selectively operable in a seventh working state with one of the end elements in the outward state, and the other one of the end elements in one of the second forward state and the second rearward state.

Ideally, the end elements are selectively operable in an eighth working state with both of the end elements in the second forward state.

Preferably, the end elements are selectively operable in a ninth working state with both of the end elements in the second rearward state.

In one aspect of the invention each end element is operable from the first forward state to the first rearward state through the second forward state, the outward state and the second rearward state.

In another aspect of the invention the end elements are urgeable between the first forward state and the first rearward state independently of each other.

In a further aspect of the invention each end element is pivotally coupled relative to the plough blade about a main pivot axis, and is pivotal between the first forward state and the first rearward state about the main pivot axis.

In one aspect of the invention the main pivot axis, about which each end element is pivotally coupled relative to the plough blade, comprises a substantially horizontally extending main pivot axis.

In an alternative aspect of the invention the main pivot axis, about which each end element is pivotally coupled relative to the plough blade, comprises a substantially vertically extending main pivot axis.

In one aspect of the invention a main urging means is provided for urging the end elements between the first forward state and the first rearward state.

Preferably, a pair of the main urging means is provided, one main urging means being provided for each end element.

In one aspect of the invention each main urging means is configured to act between the plough blade and the corresponding end element.

In another aspect of the invention each main urging means is coupled to one of the plough blade and the corresponding end element through a linkage.

In another aspect of the invention each main urging means is coupled to the corresponding end element through the corresponding linkage.

In a further aspect of the invention each main urging means is coupled to the plough blade.

In one aspect of the invention each main urging means comprises a main urging ram.

In another aspect of the invention each end element comprises an extension blade. Preferably, each end element comprises a plate member. Advantageously, each end element comprises a planar plate member.

Alternatively, each end element is of arcuate cross-sectional shape.

In another aspect of the invention the transverse cross-section of each end element is substantially similar to the transverse cross-section of the plough blade.

In a further aspect of the invention the plough blade is of arcuate transverse cross-section.

Preferably, the plough blade is urgeable relative to the support element between a lower operative state engageable with material to be ploughed and an upper inoperative state raised above the material.

Advantageously, the brush is urgeable relative to the support element between a lower operative state for brushing material from a surface and an upper inoperative state raised above the surface.

Preferably, the plough blade and the brush are alternately operable in the operative state and the inoperative state, so that when one of the brush and the plough blade is in the operative state thereof, the other one of the brush and the plough blade is in the inoperative state thereof.

Advantageously, the plough blade and the brush are simultaneously operable in the respective inoperative states.

Advantageously, the plough blade and the brush are simultaneously operable in the operative state.

In one aspect of the invention a first actuator means is provided for urging the plough blade relative to the support element between the operative state and the inoperative state thereof.

In another aspect of the invention a second actuator means is provided for urging the brush relative to the support element between the operative state and the inoperative state thereof.

Preferably, the coupling means comprises a mounting element adapted for coupling to the prime mover and a load bearing arm coupling the support element to the mounting element.

In one aspect of the invention the load bearing arm is pivotally coupled to the mounting element about a substantially vertically extending first pivot axis, and is pivotally coupled to the support element about a substantially vertically extending second pivot axis.

In another aspect of the invention a link arm is pivotally coupled to the first mounting element about a substantially vertically extending third pivot axis and is pivotally coupled to the support element about a substantially vertically extending fourth pivot axis, the first and third pivot axes being spaced apart from each other, and the second and fourth pivot axes being spaced apart from each other.

In a further aspect of the invention the spacing between the first and third pivot axes is different to the spacing between the second and fourth pivot axes for controlling movement of the support element relative to the prime mover between the transverse state and the maximum offset state so that the plough blade remains substantially within the tracks defined by wheels of the prime mover as the support element is being urged between the transverse state and the maximum offset state.

Preferably, a third actuator means is provided for urging the support element between the transverse state and the maximum offset state.

In one aspect of the invention the third actuator means comprises an actuator ram configured to act between one of the mounting element and the support element, and one of the load bearing arms and the link arm.

In another aspect of the invention the prime mover comprises a wheeled work vehicle.

In another aspect of the invention the wheeled work vehicle comprises a forward part and a rearward part pivotally coupled together about a substantially vertically extending pivot axis for facilitating steering of the wheeled work vehicle.

The invention also provides a prime mover comprising the attachment according to the invention.

In one aspect of the invention the prime mover comprises a wheeled work vehicle.

In another aspect of the invention the wheeled work vehicle comprises a forward part and a rearward part pivotally coupled together about a substantially vertically extending pivot axis for facilitating steering of the wheeled work vehicle.

Additionally the invention provides a method for operating an attachment coupled to a prime mover by a coupling means, wherein the attachment comprises a support element, an elongated generally transversely extending cylindrical brush rotatably mounted in the support element about a substantially transversely extending rotational axis, an elongated generally transversely extending plough blade supported on the support element, a pair of end elements located at respective opposite ends of the plough blade, each end element being selectively operable relative to the plough blade in at least a first forward state extending generally forwardly and substantially perpendicularly from the plough blade and a first rearward state extending generally rearwardly and substantially perpendicularly from the plough blade, the method comprising operating the coupling means to set the support element in a transverse state with the plough blade and the brush extending substantially transversely relative to the direction of normal forward motion of the prime mover, and operating the end elements into one of a first working state with both of the end elements in the first forward state, a second working state with both of the end elements in the first rearward state, and a third working state with one of the end elements in the first forward state and the other one of the end elements in the first rearward state.

Preferably, each end element is selectively operable in an outward state with the end element extending generally outwardly from the plough blade and substantially longitudinally aligned with the plough blade.

Advantageously, the end elements are selectively operated in a fourth working state with one of the end elements in the outward state and the other one of the end elements in one of the first forward state and the first rearward state.

In one aspect of the invention the end elements are selectively operated in a fifth working state with both the end elements in the outward state.

In another aspect of the invention each end element is selectively operated in one of a plurality of intermediate states between the first forward state and the first rearward state.

Preferably, the coupling means is selectively operable in one of the transverse state with the plough blade and the brush in the transverse state extending substantially transversely of the direction of normal forward motion of the prime mover and a maximum offset state with the plough blade and the brush in a maximum offset angled state offset at an angle greater than zero from the transverse state thereof.

In one aspect of the invention the support housing is selectively operable into one of a plurality of offset states between the transverse state thereof and the maximum offset state thereof with the plough blade and the brush in a corresponding offset angled state.

In another aspect of the invention each end element is selectively operable in a second forward state extending from the plough blade generally forwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state, and each end element is selectively operable in a second rearward state extending from the plough blade generally rearwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state.

In another aspect of the invention the end elements are selectively operated in a sixth working state with one of the end elements in the second forward state, and the other one of the end elements in the second rearward state.

In a further aspect of the invention the end elements are selectively operated in a seventh working state with one of the end elements in the outward state, and the other one of the end elements in one of the second forward state and the second rearward state.

In a further aspect of the invention the end elements are selectively operated in an eighth working state with both of the end elements in the second forward state.

In another aspect of the invention the end elements are selectively operated in a ninth working state with both of the end elements in the second rearward state.

In one aspect of the invention the plough blade is selectively urgeable relative to the support element into a lower operative state engageable with material to be ploughed from an upper inoperative state raised above the material.

In another aspect of the invention the brush is selectively urgeable relative to the support element into a lower operative state for brushing material from a surface to an upper inoperative state raised above the surface.

Preferably, the plough blade and the brush are alternately operated in the operative state and the inoperative state, so that when one of the brush and the plough blade is in the operative state thereof, the other one of the brush and the plough blade is in the inoperative state thereof.

Advantageously, the plough blade and the brush are simultaneously operated in the respective inoperative states.

Advantageously, the plough blade and the brush are simultaneously operated in the operative state.

The advantages of the invention are many. A particularly important advantage of the attachment according to the invention is that the support element is operable in both a transverse state, and a plurality of offset states up to the respective maximum offset states, and thus, the support element is operable from one maximum offset state to the other maximum offset state through the transverse state. This advantage provides the further advantage that as the support element is operated from one maximum offset state through the transverse state to the other one of the maximum offset states, the plough blade and the brush are correspondingly operated from their respective maximum offset angled states through their respective transverse states to the other ones of their respective maximum offset angled states. Additionally, when the plough blade is in the transverse state, the end elements of the plough blade may be operable in a plurality of working states with both of the end elements extending in the first forward state, both of the end elements extending in the first rearward state or with one of the end elements extending in the first forward state and the other in the first rearward state. Additionally, with the support element slewed into one of the offset states with the plough blade in the corresponding offset angled state, the end elements may be operated in a plurality of further working states with both end elements extending in either the second forward or the second rearward states extending generally forwardly or generally rearwardly relative to the plough blade and parallel to the direction of normal forward motion of the prime mover. Further, the end elements may be operated in a number of other working states with both of the end elements extending in one of the second forward states, or with both of the end elements extending in one of the second rearward states, or with one of the end elements extending in one of the second forward states and the other end element extending in one of the second rearward states, or with both of the end elements in the outward state extending outwardly of the plough blade and substantially aligned therewith, or with one of the end elements in the outward state and the other one of the end elements extending in either the second forward state or the second rearward state, or in the first forward state or the first rearward state.

A further advantage of the invention is achieved by virtue of the fact that the plough blade is operable between an operative state adjacent the ground, and an inoperative state raised above and spaced apart from the ground, and also the fact that the brush is operable between an operative state engaging the ground and an inoperative state raised above and spaced apart above the ground. This provides the advantage that the plough blade can be operated in the operative state with the brush in the inoperative state, and vice versa with the plough blade in the inoperative state and the brush in the operative state. Additionally, both the brush and the plough blade can be operated simultaneously in the operative states, and also can be operated simultaneously in the inoperative states.

A particularly important advantage of the invention is that it provides a single attachment for a prime mover, which can be operated to collect material when the plough blade and the end elements are operated as a box plough, to spill material at one or both ends of the plough blade, and to sweep material.

The invention will be more clearly understood from the following description of some preferred embodiments thereof, which are given by way of example only, with reference to the accompanying drawings, in which:

FIG. 1 is a top plan view of a prime mover according to the invention comprising an attachment also according to the invention forwardly coupled to the prime mover for clearing material, such as snow and other debris on a road, an airport runway, an apron of an airport on which aircraft stand and any other areas where it is desired to clear snow and other debris,

FIG. 2 is a top plan view of the prime mover and the attachment of FIG. 1 illustrating the attachment in a different state to that of FIG. 1,

FIG. 3 is a top plan view of a prime mover and the attachment of FIG. 1 illustrating the attachment in another different state to that of FIG. 1,

FIG. 4 is an enlarged top plan view of the attachment of FIG. 1 illustrated in the state of FIG. 1,

FIG. 5 is a side elevational view of the attachment of FIG. 1 in the state of FIG. 1,

FIG. 6 is a side elevational view of the attachment of FIG. 1 in the state of FIG. 1 with a portion of the attachment in a different state to that of FIG. 1,

FIG. 7 is a front elevational view of the attachment of FIG. 1,

FIG. 8 is a front elevational view of the attachment of FIG. 1 with portions of the attachment in the state of FIG. 6,

FIG. 9 is a side elevational view of the attachment of FIG. 1 with a portion of the attachment in a different state to that of FIG. 1,

FIG. 10 is a front elevational view of the attachment of FIG. 1 with the portion of FIG. 9 in the state of FIG. 9,

FIGS. 11(a) to 11(l) are schematic top plan views of the attachment of FIG. 1 with portions of the attachment in respective different states,

FIG. 12 is a top plan view of a prime mover and an attachment according to another embodiment of the invention,

FIG. 13 is a top plan view of the prime mover and the attachment of FIG. 12 with the attachment in a different state to that of FIG. 12,

FIG. 14 is a top plan view of the prime mover and the attachment of FIG. 12 with the attachment in a different state to that of FIG. 12,

FIG. 15 is a top plan view of the attachment of FIG. 12,

FIG. 16 is another top plan view of the attachment of FIG. 12,

FIG. 17 is another top plan view of the attachment of FIG. 12,

FIG. 18 is another top plan view of the attachment of FIG. 12,

FIG. 19 is another top plan view of the attachment of FIG. 12,

FIG. 20 is a side elevational view of the attachment of FIG. 12,

FIG. 21 is another side elevational view of the attachment of FIG. 12,

FIG. 22 is another side elevational view of the attachment of FIG. 12,

FIG. 23 is another side elevational view of the attachment of FIG. 12,

FIG. 24 is a front elevational view of the attachment of FIG. 12,

FIG. 25 is another front elevational view of the attachment of FIG. 12,

FIG. 26 is another front elevational view of the attachment of FIG. 12,

FIGS. 27(a) to 27(r) are schematic top plan views of the attachment of FIG. 12 in a plurality of different states,

The drawings are not to scale, and for convenience various parts have been omitted from some of the drawings. In general, the drawings show various parts of the attachment in different states in which the attachment is operable, but not all operable states of the attachment are illustrated.

Referring now to FIGS. 1 to 11 of the drawings, there is illustrated an attachment according to the invention, indicated generally by the reference numeral 1, for attaching to a prime mover, in this case a wheeled work vehicle 2. The attachment 1 is particularly suitable for clearing material, such as snow or other debris from a road, an airport runway or an airport apron on which aircraft stand. The attachment 1 comprises a support element, namely, a support housing 3, an elongated plough blade 4 mounted on the support housing 3 for clearing snow or other debris, and an elongated cylindrical brush 5 rotatably mounted in the support housing 3 about a geometrical central rotational axis 6 for brushing the material such as snow and other debris. The support housing 3, the plough blade 4 and the brush 5 will be described in detail below. A coupling means comprising a coupling mechanism 7, which will also be described below, couples the attachment 1 to the front 8 of the wheeled work vehicle 2.

The wheeled work vehicle 2 comprises a forward part 9 and a rearward part 10 which are pivotally coupled together about a substantially vertically extending pivot axis 11 for facilitating steering of the wheeled work vehicle 2. Such wheeled work vehicles as the wheeled work vehicle 2 will be well known to those skilled in the art, and further description should not be required.

The plough blade 4 is of arcuate transverse cross-section, which for convenience in the drawings is illustrated as being of planar transverse cross-section, although the plough blade 40 may be a planar plough blade. A pair of first carrier arms 12 extending rearwardly from the plough blade 4 adjacent respective opposite ends 15 and 16 thereof are pivotally carried on the support housing 3 on respective pivot shafts 17. The pivot shafts 17 define a common first pivot axis 18 about which the plough blade 4 is pivotal relative to the support housing 3 between a lower operative state, illustrated in FIG. 5 for engaging material on the ground to be ploughed, and an upper inoperative state illustrated in FIG. 9 spaced apart above the ground. The pivot shafts 17 are configured so that the first pivot axis 18 extends parallel to the rotational axis 6 of the brush 5, and the plough blade 4 extends parallel to the rotational axis 6 of the brush 5. A first actuator means, namely, a pair of hydraulically powered blade actuator rams 19 acting between the support housing 3 and the respective first carrier arms 12 on respective opposite ends of the support housing 3 urge the plough blade 14 between the lower operative state and the upper inoperative state. One of the blade actuator rams 19 is illustrated in FIG. 5.

A pair of second carrier arms 20 are pivotally carried on the support housing 3 at respective opposite ends thereof on pivot shafts 22. The second carrier arms 20 rotatably carry a brush shaft 24 in bearings (not shown), and the brush 5 is rigidly mounted on and coaxial with the brush shaft 24. The brush shaft 24 defines the rotational axis 6 about which the brush 5 is rotatable in the support housing 3. The pivot shafts 22 define a common second pivot axis 25 about which the brush 5 is pivotal between a lower operative state, illustrated in FIG. 9, engageable with the ground for brushing material along the ground, and an upper inoperative state, illustrated in FIG. 5 spaced apart above the ground. A pair of second actuator means, namely, a pair of hydraulically operated brush actuator rams 27 acting between the support housing 3 and the second carrier arms 20 on respective opposite ends of the support housing 3 urge the second carrier arms 20, and in turn the brush 5 about the second pivot axis 25 between the lower operative state and the upper inoperative state. One of the brush actuator rams 27 is illustrated in FIG. 5.

In this embodiment of the invention the blade and the brush actuator rams 19 and 27 are operable for selectively urging the plough blade 4 and the brush 5 alternately into the operative state and the inoperative state, so that when one of the plough blade 4 and the brush 5 is in the operative state, the other one of the plough blade 4 and the brush 5 is in the inoperative state. Additionally, the blade and the brush actuator rams 19 and 27 are operable for simultaneously operating the plough blade 4 and the brush 5 into the inoperative state for allowing the attachment 1 to be transported from one site to another with both the plough blade 4 and the brush 5 in the upper inoperative states. The blade and the brush actuator rams 19 and 27 are also operable for urging the plough blade 4 and the brush 5 simultaneously into the lower operative state, so that the brush 5 can brush any remaining material on and in a path cleared by the plough blade 4 as the attachment 1 is being urged forwardly in the direction of the arrow A by the wheeled work vehicle 2.

A drive motor 29 illustrated in FIG. 5 is carried on one of the second carrier arms 20 and drives the brush shaft 24 through a chain and sprocket drive transmission 30 for in turn rotating the brush 5 about the rotational axis 6.

The coupling mechanism 7 for coupling the support housing 3 to the wheeled work vehicle 2 comprises a mounting element 32 for releasably coupling to the front end 8 of the forward part 9 of the wheeled work vehicle 2. A load bearing carrier arm 35 which extends forwardly from the mounting element 32 is pivotally coupled to the mounting element 32 about a substantially vertically extending first vertical pivot axis 36. The support housing 3 is pivotally coupled to the load bearing carrier arm 35 about a substantially vertically extending second vertical pivot axis 37 which substantially cuts the rotational axis 6 about which the cylindrical brush 5 is rotatable.

The support housing 3 is coupled to the mounting element 32 by the load bearing arm 35, so that the support housing 3 is slewable from a transverse state illustrated in FIG. 1 with the support housing 3 extending substantially transversely of the direction of normal forward motion of the wheeled work vehicle 2, which is indicated by the arrow A, to either one of a pair of maximum offset states with the support housing 3 extending at an offset angle α relative to the transverse state of the support housing 3. The support housing 3 is illustrated in one of the maximum offset states in FIG. 2 and in the other one of the maximum offset states in FIG. 3.

In this embodiment of the invention the maximum value of the angle α through which the support housing 3 is slewed from the transverse state to each one of the maximum offset states is approximately 30°, and thus, the maximum angle through which the support housing 3 is slewable from one of the maximum offset states to the other one of the maximum offset states is 60°. In the transverse state of the support housing 3, the plough blade 4 and the brush 5 are also in a transverse state extending substantially transversely relative to the direction of the normal forward motion of the wheeled work vehicle 3. In the maximum offset states of the support housing 3, the plough blade 4 and the brush 5 are in corresponding maximum offset angled states with the plough blade 4 and the brush 5 extending at a maximum offset angle θ offset from the transverse states of the respective plough blade 4 and brush 5. The value of the maximum offset angle θ is similar to the maximum value of the offset angle α, namely, approximately 30°.

A link arm 38 illustrated in FIGS. 1 and 5 extends between the mounting element 32 and the support housing 3 and is pivotally coupled to the mounting element 32 and the support housing 3 about respective substantially vertically extending third and fourth vertical pivot axes 39 and 40, respectively. The third and fourth pivot axes 39 and 40 are spaced apart from the first and second pivot axes 36 and 37 of the load bearing carrier arm 35 for controlling slewing of the support housing 3 relative to the mounting element 32 from a transverse state illustrated in FIG. 1 to the respective maximum offset states illustrated in FIGS. 2 and 3.

A third actuator means, in this embodiment of the invention comprising an hydraulically powered slewing actuator ram 42 illustrated in FIG. 1 is coupled between the support housing 3 and the load bearing carrier arm 35 for slewing the support housing 3 between the transverse state and the respective maximum offset states. The slewing actuator ram 42 is also configured to operate under the control of a suitable hydraulic control circuit (not shown) for slewing the support housing 3 into a plurality of intermediate offset states between the transverse state and the respective maximum offset states.

The spacing between the first and the third vertical pivot axes 36 and 39 is greater than the spacing between the second and the fourth vertical pivot axes 37 and 40, so that as the support housing 3 is being slewed by the slewing actuator ram 42 between the transverse state and the maximum offset state, and in turn the plough blade 4 and the brush 5 are being slewed between the transverse state and the maximum offset angled states, the plough blade 4 and the brush 5 remain substantially within the wheel tracks defined by ground engaging wheels of the wheeled work vehicle 2 when the wheeled work vehicle 2 is being driven forwardly with rectilinear motion.

A pair of end elements 44 provided by planar end plates are pivotally coupled at the respective opposite ends 15 and 16 of the plough blade 4, and are pivotal about respective horizontally extending main pivot axes 45 between a first forward state illustrated in FIG. 1 and FIG. 11(a) extending generally forwardly from the plough blade 4 and perpendicular thereto to form a box plough, and a first rearward state illustrated in FIGS. 6 and 11(b) extending generally rearwardly from the plough blade 4 and perpendicular thereto to form a reverse box plough should it be desired to use the attachment 1 as a box plough when the wheeled work vehicle 2 is operating in reverse, or to spill material from one or both ends 15 and 16 of the plough blade 4 when the attachment 1 is being urged forwardly in the direction of the arrow A by the wheeled work vehicle 2.

A mounting bracket 49 extends from each end element 44 for coupling the end element 44 to the plough blade 4 adjacent the corresponding end 15 or 16 thereof. Carrier brackets 47 extending rearwardly from the plough blade 4 at the respective opposite ends 15 and 16 thereof pivotally carry respective main pivot shafts 48, which extend from and are rigidly secured to the mounting brackets 49 of the corresponding end elements 44 for pivotally coupling the end elements 44 to the plough blade 4. The main pivot shafts 48 define the horizontally extending main pivot axes 45 about which the end elements 44 are pivotal between the first forward state and the first rearward state. The two main pivot axes 45 coincide with each other, although this is not essential. Each end element 44 and its corresponding mounting bracket 49 are formed by a plate member of steel plate material and are substantially planar.

Main urging means comprising a pair of hydraulically powered main urging rams 50 act between the plough blade 4 and the respective end elements 44 for urging the end elements 44 independently of each other between the first forward and first rearward states. One of the main urging rams 50 is illustrated in FIGS. 5 and 6. Each main urging ram 50 is pivotally coupled to the plough blade 4 adjacent the rear thereof by a mounting bracket 43, and is coupled to the main pivot shaft 48 of the corresponding end element 44 through a linkage, namely, a link member 46. One of the link members is illustrated in FIGS. 5 and 6. One end of each link member 46 is pivotally coupled to the corresponding main urging ram 50, and the other end of each link member 46 is pivotally coupled to the main pivot shaft 48.

Additionally, the main urging rams 50 are operable for in turn operating the end elements 44 relative to the plough blade 4 between a plurality of selectable working states, in this case three selectable working states, namely, a first working state in which the respective end elements 44 are both in the first forward state extending forwardly from the plough blade 4 to form with the plough blade 4 the box plough as illustrated in FIGS. 1 and 11(a), a second working state in which both of the end elements 44 are in the first rearward state extending rearwardly from the plough blade 4 either to form a reverse box plough or for facilitating spilling of material from the plough blade 4 at one or both of the respective opposite ends 15 and 16 of the plough blade 4, see FIGS. 6 and 11(b) and a third working state illustrated in FIGS. 11(c) and (d) in which one of the end elements 44 is in the first forward state extending forwardly from the plough blade 4, and the other one of the end elements 44 is in the first rearward state extending rearwardly from the plough blade 4 to facilitate spilling of the material from the plough blade 4 at the one of the ends 15 and 16 thereof, in which the end element 44 is in the first rearward state. For example, in the configuration illustrated in FIG. 11(c) the end element 44 at the end 15 of the plough blade 4 is in the first rearward state, so that material can be spilt from the plough blade 4 at the end 15. The end element 44 at the end 16 of the plough blade 4, which is in the first forward state in FIG. 11(c) prevents material being spilled from the plough blade 4 at the end 16 thereof.

Typically, when the end elements 44 are operated in the third working state, in other words, with one of the end elements 44 in the first forward state, and the other one of the end elements 44 in the first rearward state, when the support housing 3 is being operated in one of the offset states with the plough blade 4 in the corresponding offset angled state, the end element 44 adjacent the one of the ends 15 and 16 of the plough blade 4 which is the leading end of the plough blade 4 is operated in the first forward state, and the end element 44 adjacent the other one of the ends 15 and 16 which is the trailing end of the plough blade 4 is operated in the first rearward state, see for example FIG. 11(g) in which the end 16 is the leading end of the plough blade 4, and the end element 44 thereof is in the first forward state, and the end 15 is the trailing end of the plough blade 4, and the end element 44 thereof is in the first rearward state.

In use, with the attachment 1 coupled to the wheeled work vehicle 2 by the coupling mechanism 7, and the blade, brush and slewing actuator rams 19, 27 and 42 and the main urging rams 50 connected to the hydraulic system of the wheeled work vehicle 2, the wheeled work vehicle 2 and the attachment 1 are ready for use. The support housing 3 is set either in the transverse state with the plough blade 4 and the brush 5 also in the transverse states extending transversely of the direction of normal forward motion of the wheeled work vehicle 2, or the support housing 3 may be slewed relative to the wheeled work vehicle 2 by the slewing actuator ram 42 into one of the offset states with the plough blade 4 and the brush 5 in the corresponding offset angled states extending at a desired offset angle relative to the transverse state of the plough blade 4 and the brush 5. The support housing 3 may be slewed into any desired offset state up to and including either one of the maximum offset states, with the plough blade 4 and the brush 5 in the corresponding offset angled state up to the corresponding maximum offset angled state of approximately 30° to the transverse state.

When the support housing 3 has been set in either the transverse state or the desired offset state, and when it is desired to use the plough blade 4 as a box plough, the end elements 44 are operated into the first working state with the end elements 44 in the first forward state extending generally forwardly and perpendicularly from the plough blade 4. The plough blade 4 is then lowered into the operative state, and generally the brush 5 is raised into the inoperative state. When it is desired to use the plough blade 4 as a reverse box plough or to spill material from both ends 15 and 16 of the plough blade 4, the end elements 44 are operated into the second working state, with the two end elements 44 in the first rearward state.

When it is desired to spill material being ploughed from one of the ends 15 and 16 only of the plough blade 4, the end elements 44 are operated into the third working state with the end element 44 at the end of the plough blade 4 from which material is to be spilled in the first rearward state and the end element 44 at the other end of the plough blade 4 in the first forward state.

Typically, when it is desired to spill material from one of the ends 15 and 16 of the plough blade 4, the support housing 3 is slewed by the slewing actuator ram 42 into a selected one of the offset states, and the end element 44 adjacent the end 15 or 16, which is the leading end of the plough blade 4 is operated into the first forward state, while the end element 44 at the trailing end of the plough blade 4 is operated into the first rearward state. Alternatively, when it is desired to spill material from one of the ends 15 and 16 of the plough blade 4, the support housing 3 may be slewed by the slewing actuator ram 42 into a selected one of the offset states, and both of the end elements 44 could be operated into the first rearward state, and in which case, material would normally be spilt only from the end 15 or 16 of the plough blade 4 which is the trailing end of the plough blade 4.

When it is desired to operate the attachment 1 for brushing or sweeping material along the ground forwardly of the direction of normal forward movement of the wheeled work vehicle 2, the brush 5 is lowered into the operative state, and the plough blade 4 is raised into the inoperative state. The brush 5 is rotated in the direction of the arrow B by the motor 29, and as the wheeled work vehicle 2 is driven forwardly along the ground urging the brush 5 forwardly, with the brush 5 rotating in the direction of the arrow B, material on the ground is swept forwardly as the wheeled work vehicle 2 progresses forwardly in the direction of the arrow A.

When it is desired to operate the brush 5 to sweep material remaining on the ground in the path of the plough blade 4 as the plough blade 4 is being urged forwardly by the wheeled work vehicle 2, both the plough blade 4 and the brush 5 are lowered into their respective operative states. Thus, as the attachment 1 is being urged forwardly in the direction of the arrow A by the wheeled work vehicle 2, with the brush 5 rotating in the direction of the arrow B, any material remaining on the ground in the path of the plough blade 4 is swept forwardly by the brush 5 as the attachment 1 is being urged forwardly by the wheeled work vehicle 2.

Should it be desired to drive the wheeled work vehicle from one site to another, both the plough blade 4 and the brush 5 are raised into their respective operative states, and the wheeled work vehicle 2 is then driven from one site to the next.

Referring now to FIGS. 12 to 27, there is illustrated an attachment according to another embodiment of the invention, indicated generally by the reference numeral 60, also for mounting on a prime mover, for example, the wheeled work vehicle 2. The attachment 60 is substantially similar to the attachment 1, and similar components are identified by the same reference numerals. The attachment 60 is also suitable for clearing material such as snow or other debris from a road, an airport runway or an airport apron on which aircraft stand.

In this embodiment of the invention the coupling mechanism 7 is also configured to operate the support housing 3 from the transverse state through a plurality of offset states to the two maximum offset states, and in this embodiment of the invention the coupling mechanism 7 is configured to operate the support housing 3 through the maximum angle α of approximately 35° from the transverse state into each one of the maximum offset states. Thus, as the support housing 3 is slewed between the two maximum offset states, the support housing 3 is slewed through an angle of 70°, and the plough blade 4 is also slewed through an angle of 70°.

The main difference between the attachment 60 and the attachment 1 is in the end elements of the plough blade 4, which in this embodiment of the invention are identified by the reference numeral 62 and are also provided as end blades, each of which comprises a planar plate member of steel plate material. The end elements 62 are pivotally coupled to the plough blade 4 adjacent the respective opposite ends 15 and 16 of the plough blade 4. However, in this embodiment of the invention the end elements 62 are pivotally coupled to the plough blade 4 about respective vertically extending main pivot axes 64. Mounting brackets 65 extending outwardly from the plough blade 4 adjacent the respective opposite ends 15 and 16 carry respective vertically extending main pivot shafts 66 which pivotally carry the end elements 62, and define the vertically extending main pivot axes 64 about which the end elements 62 are pivotal relative to the plough blade 4.

In this embodiment of the invention the end elements 62, since they are pivotal about respective vertically extending main pivot axes are pivotal from the first forward state to the first rearward state, which are similar to the first forward state and the first rearward state of the end elements 44 of the attachment 1. However, in this embodiment of the invention the end elements 62 are pivotal from the first forward state to the second forward state through respective outward states, with the end elements 62 extending outwardly from and aligned with the plough blade 4. In FIG. 16 the end elements 62 at both ends 15 and 16 of the plough blade 4 are illustrated in the outward state.

When the support housing 3 is in one of the offset states, including either one of the maximum offset states, with the plough blade 4 in the corresponding one of the offset angled state, the end element 62 which is located at the leading one of the ends 15 and 16 of the plough blade 4 may be operated in a second forward state with the end element 62 extending generally forwardly from the plough blade 4 and substantially parallel to the direction of normal forward motion of the wheeled work vehicle 2, namely, the direction of the arrow A, and the other one of the end elements 62 which is adjacent the trailing one of the ends 15 and 16 of the plough blade 4 may be operated in a second rearward state with the end element 62 extending generally rearwardly from the plough blade 4 and substantially parallel to the normal forward direction of the wheeled work vehicle 2.

Since the support housing 3 is operable between a plurality of offset states from the transverse state to each one of the maximum offset states, and since the plough blade 4 is similarly operable through a plurality of offset angled states from the transverse state to each one of the maximum offset angled states, each end element 62 is operable into a plurality of second forward states, and second rearward states corresponding to the offset angled state of the plough blade 4. Thus, in this embodiment of the invention as each end element 62 is being pivoted from the first forward state to the first rearward state, the end element 62 pivots through any one of the second forward state, the outward state and any one of the second rearward state, depending on the offset state of the support housing 3.

In FIG. 18 the support housing 3 is illustrated in one of the offset states and the plough blade 4 is illustrated in the corresponding one of the offset angled states. Also in FIG. 18 the end element 62 adjacent the leading end 16 of the plough blade 4 is illustrated in full lines in the corresponding second forward state, and the end element 62 adjacent the trailing end 15 of the plough blade 4 is illustrated in full lines in the corresponding second rearward state.

Main urging means, in this embodiment of the invention main urging rams 67 acting between the plough blade 4 and the respective end elements 62 selectively and independently pivot the end blade 62 between the respective first forward states and first rearward states, which are similar to the first forward state and the first rearward state of the end elements 44, with each end element 62, when in the first forward state extending generally forwardly and perpendicularly from the plough blade 4, and when in the first rearward state extending generally rearwardly and perpendicularly from the plough blade 4. Each first urging ram 67 is pivotally coupled to the plough blade 4 by a corresponding mounting bracket 68, and each main urging ram 67 is coupled to the corresponding end element 62 through a linkage 63. One end of each linkage 63 is pivotally coupled to the corresponding main urging ram 67, and the other end of each linkage 63 is pivotally coupled to the corresponding end element 62 by a mounting bracket 69 secured to the end element 62. The main urging rams 67 and the linkages 62 are illustrated in some of the drawings only.

When the support housing 3 is in one of the offset states and the plough blade 4 is in the corresponding one of the offset angled states, the main urging rams 67 are operable for urging the end element 62 at the leading one of the ends 15 and 16 of the plough blade 4 into the second forward state, and the end element 62 at the trailing one of the ends 15 and 16 of the plough blade 4 into the second rearward state.

The first urging rams 67 are also operable for urging the end elements 62 into the respective outward states with the end elements 62 extending outwardly from either or both of the ends 15 and 16 of the plough blade 4 and substantially aligned with the plough blade 4 irrespective of the state of the support housing 3 and the plough blade 4, in other words, irrespective of whether the plough blade 4 is in the transverse state or in any one of the offset angled states.

Accordingly, in this embodiment of the invention the plough blade 4 and the end elements 62 are operable in nine different working states as follows:

-   -   (a) a first working state similar to the first working state of         the end elements 44 of the attachment 1 with both of the end         elements 62 in the first forward state. Typically, in this         embodiment of the invention the end elements 62 are operable in         the first working state when the support housing 3 is in the         transverse state and the plough blade 4 is in the transverse         state, see FIG. 12,     -   (b) a second working state which is similar to the second         working state of the end elements 44 of the attachment 1, with         both of the end elements 62 in the first rearward state. In         general, in this embodiment of the invention the end elements 62         would be operated in the second working state when the support         housing 3 is in the transverse state and the plough blade 4 is         in the transverse state, see FIG. 17,     -   (c) a third working state which is similar to the third working         state of the end elements 44 of the attachment 1, with one of         the end elements 62 in the first forward state and the other one         of the end elements 62 in the first rearward state. Typically,         the end elements 62 would be operated in the third working state         when the support housing 3 and the plough blade 4 are in the         respective transverse states. Although it will be appreciated         that the plough blade 4 and the end elements 62 may be operated         in the third working state with the support housing 3 in one of         the offset states, and the plough blade 4 in the corresponding         one of the offset angled states.     -   (d) a fourth working state with one of the end elements 62 in         the outward state, and the other one of the end elements in one         of the first forward state and the first rearward state.         Typically, the end elements 62 would be operated in the fourth         working state when the support housing 3 and the plough blade 4         are in the transverse state. Although it will be readily         appreciated that the end elements 62 may be operated in the         fourth working state with the support housing 3 in one of the         offset states and the plough blade 4 in the corresponding one of         the offset angled states,     -   (e) a fifth working state with the end elements 62 both in the         outward states, see FIG. 16. The plough blade 4 and the end         elements 62 may be operated in the fifth working state both when         the support housing 3 and the plough blade 4 are in the         transverse states, and when the support housing 3 is in one of         the offset states and the plough blade 4 is in the corresponding         one of the offset angled states,     -   (f) a sixth working state with one of the end elements 62 in the         second forward state, and the other one of the end elements in         the second rearward state, see FIGS. 18 and 19. The end elements         62 would be operated in the sixth working state when the support         housing 3 is in one of the offset states, and the plough blade 4         is in a corresponding one of the offset angled states,     -   (g) a seventh working state with one of the end elements 62 in         the outward state, and the other one of the end elements 62 in         one of the second forward state and second rearward state, see         FIG. 14. The end elements 62 would be operated in the seventh         working state when the support housing 3 is in one of the offset         states and the plough blade 4 is in a corresponding one of the         offset angled states,     -   (h) an eighth working state with both the end element 62         adjacent the leading one of the ends 15 and 16 of the plough         blade 4 in the second forward state, and the end element 62         adjacent the trailing one of the ends 15 and 16 of the plough         blade 4 in the first forward state, see FIGS. 27(a) and 270).         The end elements 62 would be operated in the eighth working         state when the support housing 3 is in one of the offset states         and the plough blade 4 is in the corresponding one of the angled         offset states,     -   (i) a ninth working state with the end element 62 adjacent the         trailing one of the ends 15 and 16 of the plough blade 4 in the         second rearward state, and the end element 62 adjacent the         leading one of the ends 15 and 16 of the plough blade 4 in the         first rearward state, see FIGS. 27(b) and 27(k).

Needless to say, there are many other working states in which the end elements 62 may be operated, some of which are illustrated in FIGS. 27(a) to 27(r) and others are illustrated in FIGS. 11(a) to 11(l).

In use, with the attachment 1 coupled to the wheeled work vehicle 2 by the coupling mechanism 7, and with the blade actuator ram 19, the brush actuator ram 27 and the slewing ram 42 and the main urging rams 67 coupled to the hydraulic system of the wheeled work vehicle 2, the attachment 60 is ready for use. When it is desired to operate the attachment 1 with the support housing 3 in the transverse state with the plough blade 4 also in the transverse state, if it is desired to operate the plough blade 4 as a box plough, the first urging rams 67 operate the end elements 62 into the first working state with end elements 62 in the first forward states. With the support element 3 in the transverse state when it is desired to operate the plough blade 4 as a reverse box plough or to spill material from the opposite ends 15 and 16 of the plough blade 4, the end elements 62 are operated into the second working state with the end elements 62 both in the first rearward state. With the support housing 3 still in the transverse state, if it is desired to operate the plough blade 4 to spill material at one of the ends 15 and 16, the end elements 62 are operated into the third working state with the end elements 62 adjacent the end 15 or 16 of the plough blade 4 from which material is to be spilled in the first rearward state, and the other one of the end elements 62 in the first forward state.

While the support housing 3 is still in the transverse state, should it be desired to extend the width of the plough blade 4 to its maximum width, the end elements 62 are operated into the fifth working state with both of the end elements extending outwardly from the plough blade 4. Additionally, with the support housing 3 in the transverse state, should it be desired to extend the plough blade 4 by the length of one of the end elements 62, the end elements 62 are operated in the fourth working state with one of the end elements 62 extending outwardly from the plough blade 4 and the other one of the end elements extending in either the first forward state or the first rearward state, depending on whether the end of the plough blade 4 adjacent the end element 62 which is being operated in the first forward state or the first rearward state is to be configured to collect material or to spill material.

When the coupling mechanism 7 is operated to set the support housing 3 in one of the offset states including one of the maximum offset states with the plough blade 4 in the corresponding one of the offset angled states, the end elements 62 may be operated in any one of the first working state to the ninth working state, and many more working states. Typically, while the attachment 60 with the support housing 3 in any one of the offset states could be operated with the end elements 62 in any one of the first, second, third and fourth working states, in general, it is more likely that with the support housing 3 in any of the offset states, the end elements 62 would most likely be operated in one of the fifth working state to the ninth working state.

With the support housing 3 in one of the offset states, and the plough blade 4 in the corresponding one of the angled offset states, if it is desired to extend the length of the plough blade by the length of two of the end plates 62, the end elements 62 are operated into the fifth working state. With the support housing 3 in one of the offset states, when it is desired to operate the plough blade 4 as either a forward box plough or a reverse box plough, the end elements 62 are operated into the either the eighth working state or the ninth working state, as appropriate.

With the support housing 3 in one of the offset states, and the plough blade 4 in the corresponding one of the offset angled states, and it is desired to extend the length of the plough blade 4 by the length of one of the end elements, the end elements 62 are operated in the seventh working state, with either the end element 62 which is at the leading end of the plough blade 4 in the second forward state or the end element 62 which is at the trailing end of the plough blade 4 in the second rearward state, and the other end element in the outward state. Whether the end element 62 is operated in the second forward state or in the second rearward state depends on whether it is desired to collect material or to allow material to be spilt.

With the support housing 3 in one of the offset states and the plough blade 4 in the corresponding one of the offset angled states, and it is desired to operate the plough blade to spill material at the trailing end thereof, and to collect material at the leading end thereof the end elements 62 are operated into the sixth working state, with the end element 62 adjacent the trailing one of the ends 15 and 16 of the plough blade 4 being operated in the second rearward state, and the other one of the end elements 62 being operated in the second forward state.

In this embodiment of the invention the blade actuator rams 19 and the brush actuator ram 27 are operable in a similar manner as the blade actuator rams 19 and the brush actuator rams 27 of the attachment 1 are operable for alternately raising and lowering the plough blade 4 and the brush 5 from the respective operative states to the respective inoperative states. Accordingly, when it is desired that the attachment 60 be operable with the plough blade 4 in the operative state adjacent the ground and the brush 5 in the inoperative state spaced apart above the ground, the blade actuator rams 19 are operated for lowering the plough blade 4 from the inoperative state to the operative state, and the brush actuator rams 27 are operated for raising the brush 5 from the operative state to the inoperative state. Alternatively, should it be desired to only sweep material by the brush 5, the plough blade 4 is operated by the blade actuator rams 19 from the operative state to the inoperative state, and the brush 5 is operated by the brush actuator rams 27 from the inoperative state to the operative state.

Should it be desired to operate the plough blade to clear material from the ground and to operate the brush to sweep any remaining material left in the path of the plough blade 7, both the plough blade 4 and the brush 5 are operated downwardly into the operative state.

Should it be desired to drive the wheeled work vehicle 2 from one site to another, both the plough blade 4 and the brush 5 are operated into the inoperative state.

While the main urging means for urging each end element about the horizontal or vertical pivot axes, as the case may be, relative to the plough blade have been described as comprising a corresponding hydraulic ram, it is envisaged that a rotary actuator, for example, an hydraulically, a pneumatically or an electrically powered rotary actuator may be provided for pivoting the end elements relative to the plough blade. Needless to say, pneumatic rams could be used instead of hydraulic rams.

While the brush has been described as being operable by a pair of hydraulically powered actuator rams between the operative and inoperative states, in certain cases, it is envisaged that a single hydraulically powered actuator ram may be sufficient for operating the brush between the operative and inoperative state. It is also envisaged that a single hydraulically powered actuator ram may be sufficient for urging the plough blade between the operative and inoperative states. Needless to say, the actuator rams may be pneumatically powered, and it is also envisaged that the brush and the plough blade may be operated between the operative and the inoperative state by an electrically powered motor which may be a rotary or a linear motor.

While the attachments have been described as comprising components which are described as being of specific materials, the components of the attachments may be of any other suitable or desired material. For example, it is envisaged that the plough blades and all the end elements may be of materials other than steel, for example, plastics material which would be suitably re-enforced or supported on a suitable re-enforced structure.

While the brush has been described as comprising an elongated cylindrical brush, the brush may be provided in a plurality of relatively short cylindrical segments abutting each other on the brush carrier shaft, or spaced apart from each other longitudinally on the brush carrier shaft.

While the prime mover has been described as being a wheeled work vehicle having a forward part and a rearward part which are pivotally coupled together about a vertical pivot axis for facilitating steering of the wheeled work vehicle, it is envisaged that the prime mover may comprise any suitable prime mover, for example, a rigid chassis prime mover, a tractor or any other suitable prime mover. It will also be appreciated that while the attachment has been described as being mounted on the forward end of the wheeled work vehicle, the attachment may be mounted on the rearward end of the wheeled work vehicle or indeed on the rear end of any other suitable prime mover.

It is envisaged in certain cases that the plough blade may be planar.

While the brush has been described as being carried on a pair of carrier arms, the brush may be carried on any suitable structure, which may be adapted for moving the brush upwardly and downwardly relative to the support housing between the operative and inoperative states, or alternatively, the mounting structure for the brush may be such that the brush would be fixedly mounted on the support housing of the attachment.

While the attachment has been described as being coupled to the wheeled work vehicle for facilitating slewing of the support housing between the transverse state and the offset state, it is envisaged that in certain cases the attachment may be coupled to the wheeled work vehicle or to any other prime mover without the support housing being slewable from a transverse state to an offset state, and in which case, the attachment would be secured to the wheeled work vehicle or other prime mover with the support housing, the plough blade and the brush in the transverse state with the brush and the plough blade extending substantially transversely relative to the direction of the normal forward motion of the prime mover, or alternatively, the attachment could be secured to the wheeled work vehicle or other prime mover with the attachment support housing in a suitable fixed offset state with the brush and the plough blade in a corresponding offset angled state extending at an offset angle greater than zero and less than 90° to the direction of the normal forward motion of the prime mover.

While the attachments have been described as being coupled to a prime mover by a coupling mechanism which is configured for slewing the support housing of the attachments between respective maximum offset states through a transverse state, it will be readily apparent to those skilled in the art that the coupling mechanisms may be configured for slewing the support housings 3 between the transverse state and one single maximum offset state. Additionally, it will be appreciated that while each maximum offset states of the support housing have been described as corresponding with a maximum angled offset state of the plough blade relative to the transverse state of the plough blade of approximately either 30° or 35°, it will be readily apparent to those skilled in the art that the maximum offset state of the support housing of the attachments may correspond with a maximum offset angled state of the plough blade relative to the transverse state of the plough blade of less than 35°, for example, an angle of 30°, an angle of 25°, an angle of 20°, or indeed, an angle of 10° relative to the transverse state of the plough blade. Needless to say, it is also envisaged that the maximum offset angled state of the plough blade may be greater than 35°, for example, 40° or even 45° relative to the transverse state of the plough blade. 

1-72. (canceled)
 73. An attachment for a prime mover, the attachment comprising a support element, an elongated generally transversely extending cylindrical brush rotatably mounted in the support element about a substantially transversely extending rotational axis, an elongated generally transversely extending plough blade supported on the support element, a pair of end elements located at respective opposite ends of the plough blade, each end element being selectively operable relative to the plough blade in at least a first forward state extending generally forwardly and substantially perpendicularly from the plough blade and a first rearward state extending generally rearwardly and substantially perpendicularly from the plough blade, the end elements being selectively operable in a first working state with both of the end elements in the first forward state, a second working state with both of the end elements in the first rearward state, and a third working state with one of the end elements in the first forward state and the other one of the end elements in the first rearward state, and a coupling means for coupling the support element to a prime mover with the support element in a transverse state and with the plough blade and the brush extending substantially transversely of the direction of normal forward motion of the prime mover.
 74. An attachment for a prime mover as claimed in claim 73 in which each end element is selectively operable in an outward state with the end element extending generally outwardly from the plough blade and substantially longitudinally aligned with the plough blade, and preferably, the end elements are selectively operable in a fourth working state with one of the end elements in the outward state and the other one of the end elements in one of the first forward state and the first rearward state, and advantageously, the end elements are selectively operable in a fifth working state with both the end elements in the outward state.
 75. An attachment for a prime mover as claimed in claim 74 in which each end element is selectively operable in a plurality of intermediate states intermediate the outward state and the first forward state, and preferably, each end element is selectively operable in a plurality of intermediate states intermediate the outward state and the first rearward state, and advantageously, each end element is selectively operable in a plurality of intermediate states between the first forward state and the first rearward state.
 76. An attachment for a prime mover as claimed in claim 73 in which the coupling means is configured for selectively setting the support element relative to the prime mover in the transverse state with the plough blade and the brush in the transverse state extending substantially transversely of the direction of normal forward motion of the prime mover and a maximum offset state with the plough blade and the brush in a maximum offset angled state offset at an angle greater than zero from the transverse state thereof, and advantageously, the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is at least 10°, and preferably, the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is at least 20°, and advantageously, the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is at least 30°, and preferably, the offset angle of the plough blade in the maximum offset angled state from the transverse state thereof is up to 35°.
 77. An attachment for a prime mover as claimed in claim 76 in which the support element is selectively operable in a plurality of offset states between the transverse state thereof and the maximum offset state thereof with the plough blade and the brush in a corresponding offset angled state, and preferably, each end element is selectively operable in a second forward state extending from the plough blade generally forwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state, and advantageously, each end element is selectively operable in a second rearward state extending from the plough blade generally rearwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state.
 78. An attachment for a prime mover as claimed in claim 76 in which the end elements are selectively operable in a sixth working state with one of the end elements in the second forward state, and the other one of the end elements in the second rearward state, and preferably, the end elements are selectively operable in a seventh working state with one of the end elements in the outward state, and the other one of the end elements in one of the second forward state and the second rearward state, and advantageously, the end elements are selectively operable in an eighth working state with both of the end elements in the second forward state, and preferably, the end elements are selectively operable in a ninth working state with both of the end elements in the second rearward state, and advantageously, each end element is operable from the first forward state to the first rearward state through the second forward state, the outward state and the second rearward state.
 79. An attachment for a prime mover as claimed in claim 73 in which the end elements are urgeable between the first forward state and the first rearward state independently of each other, and advantageously, each end element is pivotally coupled relative to the plough blade about a main pivot axis, and is pivotal between the first forward state and the first rearward state about the main pivot axis, and preferably, the main pivot axis, about which each end element is pivotally coupled relative to the plough blade, comprises a substantially horizontally extending main pivot axis, and advantageously, the main pivot axis, about which each end element is pivotally coupled relative to the plough blade, comprises a substantially vertically extending main pivot axis.
 80. An attachment for a prime mover as claimed in claim 73 in which a main urging means is provided for urging the end elements between the first forward state and the first rearward state, and preferably, a pair of the main urging means is provided, one main urging means being provided for each end element, and advantageously, each main urging means is configured to act between the plough blade and the corresponding end element, and preferably, each main urging means is coupled to one of the plough blade and the corresponding end element through a linkage, and advantageously, each main urging means is coupled to the corresponding end element through the corresponding linkage, and preferably, each main urging means is coupled to the plough blade, and advantageously, each main urging means comprises a main urging ram.
 81. An attachment for a prime mover as claimed in claim 73 in which each end element comprises an extension blade, and preferably, each end element comprises a plate member, and advantageously, each end element comprises a planar plate member.
 82. An attachment for a prime mover as claimed in claim 73 in which each end element is of arcuate cross-sectional shape.
 83. An attachment for a prime mover as claimed in claim 73 in which the transverse cross-section of each end element is substantially similar to the transverse cross-section of the plough blade, and advantageously, the plough blade is of arcuate transverse cross-section.
 84. An attachment for a prime mover as claimed in claim 73 in which the plough blade is urgeable relative to the support element between a lower operative state engageable with material to be ploughed and an upper inoperative state raised above the material, and advantageously, the brush is urgeable relative to the support element between a lower operative state for brushing material from a surface and an upper inoperative state raised above the surface, and preferably, the plough blade and the brush are alternately operable in the operative state and the inoperative state, so that when one of the brush and the plough blade is in the operative state thereof, the other one of the brush and the plough blade is in the inoperative state thereof, and advantageously, the plough blade and the brush are simultaneously operable in the respective inoperative states, and preferably, the plough blade and the brush are simultaneously operable in the operative state.
 85. An attachment for a prime mover as claimed in claim 84 in which a first actuator means is provided for urging the plough blade relative to the support element between the operative state and the inoperative state thereof, and preferably, a second actuator means is provided for urging the brush relative to the support element between the operative state and the inoperative state thereof.
 86. An attachment for a prime mover as claimed in claim 73 in which the coupling means comprises a mounting element adapted for coupling to the prime mover and a load bearing arm coupling the support element to the mounting element, and preferably, the load bearing arm is pivotally coupled to the mounting element about a substantially vertically extending first pivot axis, and is pivotally coupled to the support element about a substantially vertically extending second pivot axis, and advantageously, a link arm is pivotally coupled to the first mounting element about a substantially vertically extending third pivot axis and is pivotally coupled to the support element about a substantially vertically extending fourth pivot axis, the first and third pivot axes being spaced apart from each other, and the second and fourth pivot axes being spaced apart from each other, and preferably, the spacing between the first and third pivot axes is different to the spacing between the second and fourth pivot axes for controlling movement of the support element relative to the prime mover between the transverse state and the maximum offset state so that the plough blade remains substantially within the tracks defined by wheels of the prime mover as the support element is being urged between the transverse state and the maximum offset state, and advantageously, a third actuator means is provided for urging the support element between the transverse state and the maximum offset state, and preferably, the third actuator means comprises an actuator ram configured to act between one of the mounting element and the support element, and one of the load bearing arms and the link arm.
 87. An attachment for a prime mover as claimed in claim 73 in which the prime mover comprises a wheeled work vehicle, and preferably, the wheeled work vehicle comprises a forward part and a rearward part pivotally coupled together about a substantially vertically extending pivot axis for facilitating steering of the wheeled work vehicle.
 88. A prime mover comprising the attachment as claimed in claim 73, and preferably, the prime mover comprises a wheeled work vehicle, and advantageously, the wheeled work vehicle comprises a forward part and a rearward part pivotally coupled together about a substantially vertically extending pivot axis for facilitating steering of the wheeled work vehicle.
 89. A method for operating an attachment coupled to a prime mover by a coupling means, wherein the attachment comprises a support element, an elongated generally transversely extending cylindrical brush rotatably mounted in the support element about a substantially transversely extending rotational axis, an elongated generally transversely extending plough blade supported on the support element, a pair of end elements located at respective opposite ends of the plough blade, each end element being selectively operable relative to the plough blade in at least a first forward state extending generally forwardly and substantially perpendicularly from the plough blade and a first rearward state extending generally rearwardly and substantially perpendicularly from the plough blade, the method comprising operating the coupling means to set the support element in a transverse state with the plough blade and the brush extending substantially transversely relative to the direction of normal forward motion of the prime mover, and operating the end elements into one of a first working state with both of the end elements in the first forward state, a second working state with both of the end elements in the first rearward state, and a third working state with one of the end elements in the first forward state and the other one of the end elements in the first rearward state.
 90. A method as claimed in claim 89 in which each end element is selectively operable in an outward state with the end element extending generally outwardly from the plough blade and substantially longitudinally aligned with the plough blade, and advantageously, the end elements are selectively operated in a fourth working state with one of the end elements in the outward state and the other one of the end elements in one of the first forward state and the first rearward state, and preferably, the end elements are selectively operated in a fifth working state with both the end elements in the outward state, and advantageously, each end element is selectively operated in one of a plurality of intermediate states between the first forward state and the first rearward state.
 91. A method as claimed in claim 89 in which the coupling means is selectively operable in one of the transverse state with the plough blade and the brush in the transverse state extending substantially transversely of the direction of normal forward motion of the prime mover and a maximum offset state with the plough blade and the brush in a maximum offset angled state offset at an angle greater than zero from the transverse state thereof, and preferably, the support housing is selectively operable into one of a plurality of offset states between the transverse state thereof and the maximum offset state thereof with the plough blade and the brush in a corresponding offset angled state, and advantageously, each end element is selectively operable in a second forward state extending from the plough blade generally forwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state, and each end element is selectively operable in a second rearward state extending from the plough blade generally rearwardly and substantially parallel to the direction of normal forward motion of the prime mover when the plough blade is in one of the offset angled states up to and including the maximum offset angled state, and preferably, the end elements are selectively operated in a sixth working state with one of the end elements in the second forward state, and the other one of the end elements in the second rearward state, and preferably, the end elements are selectively operated in a seventh working state with one of the end elements in the outward state, and the other one of the end elements in one of the second forward state and the second rearward state, and advantageously, the end elements are selectively operated in an eighth working state with both of the end elements in the second forward state, and preferably, the end elements are selectively operated in a ninth working state with both of the end elements in the second rearward state.
 92. A method as claimed in claim 89 in which the plough blade is selectively urgeable relative to the support element into a lower operative state engageable with material to be ploughed from an upper inoperative state raised above the material, and preferably, the brush is selectively urgeable relative to the support element into a lower operative state for brushing material from a surface to an upper inoperative state raised above the surface, and advantageously, the plough blade and the brush are alternately operated in the operative state and the inoperative state, so that when one of the brush and the plough blade is in the operative state thereof, the other one of the brush and the plough blade is in the inoperative state thereof, and preferably, the plough blade and the brush are simultaneously operated in the respective inoperative states, and advantageously, the plough blade and the brush are simultaneously operated in the operative state. 